Abrading nib for abrading machines



July 3, 1928. 1,675,804

F. J. HOHNHORST KBRADING NIB 80R ABRADING MACHINES Filed Jan. 51. 1927 fi 7 T Patented July 3, 1928.

UNITED STATES FERDINAND J. HO HNHORST, OF C OVINGTON, KENTUCKY.

annannve NIB ron ABnAnnio MACHINES.

Application filed Jiinnar 31, 1927. Serial No. 164,831.

to provide a rotary abrading nib of novel.

construction arranged for endacontact between said nib and the grinding surface of the grindin wheel; further, to provide a rotary abrading part arranged forendwise presentation to the grindin wheel and provided with endwise holes for forming cutting edges actin on the grinding surface of the grinding wlieel with a roughing efiect for reducing the same rapidly to'cylindrical form, or rapidly reducing all parts of the grinding surface of the grinding wheel to the desired.form.

The invention will be further readily understood from the following description and claims, and from the drawings, which latter: v a 11 a Fig. 1 is an axial section of my improved device, taken on the line 1-1 of Fig. 2, showing the same mounted in anabrading machine.

Fig. 2 is a side elevation of the same.

Fig. 3 is an end elevation of my improved device. v i

Fig. at is anaXial section of the same, taken on the line H- of Fig.

Fig. 5 is an axial section of the same, taken on the line 5-5 of Fig.3,

The invention is exemplified as used in a usual grindin or polishing machine for ef- :t'ecting grin ing or polishing upon the work, for instance, in precision grinding. In machines of this character it is necessary to frequently refinish the grinding surface of the grinding wheel, as this grindin surface during use becomes dull or out o true or needs refinishing for other reasons. When refinishing the grinding surface it is frequently necessary to reshape the grinding wheel to restore its proper cylindrical. or 7 other form, and to give the grinding surface what is known as a roughing cut. The grinding surface is thereafter trued or finished in suitable manner. a

The object of the present invention is to provide novel means for producing such roughing cut in quick, accurate and convenlent manner, and preferably while the rotary grinding wheel is retained in its position and driving relation in the grinding or polishing machine. Such'machinerv is usu-' ally provided with means for causing re ciprocation of the work in opposite directions across the grinding wheel having a stationary position, or to cause reciprocations of the grinding wheel in opposite di-.

rections lengthwise of the work which has a stationary posit-ion. a i

It may be ins'tanced in the present exempllfication that the grinding wheel 11 is stationarily positioned but adjustable with re-. lation to the work, and that the Work is suitably supported and caused to rotateupon a table 12, which has reciprocations imparted thereto in suitable manner in opposite directions, so as'to move the work lengthwise in opposite directions with relation to the grinding surfaceof the rotating grinding wheel. a t

The rotary abradin part which coacts with the grinding sur .ace for roughing the same is instanced as a. nib, stub or pencil, and is hereinafter referred to as a nib, and is shown at 15. It is presented endwise toward the abrading Wheel. It is preferably normally quiescent, and has rotation imparted thereto by the rotating grinding wheel. It may be of suitable material and may for instance be a casting of metal for instance iron or steel or be of other material suitably shaped. f

Asiexemplified, it comprises an abrading 'wall 16 presented endwise to the grinding surface to be roughened. It is preferably rotated by contactof the'grindingsurface of the rotating grinding wheel with the end of said wall. a I a This end-contact preferably takes place at one sideofthe axis of rotation of the abrading nib, and the abrading nibis presentedto the grinding. surface with its axis of rota- PATENT OFFICE."

tion at anangle to a plane perpendicular to i the 1 axis of rotation of .the grinding wheel and preferably also tangential to a circle having :the 8X15 of rotation of'the grinding wheel as a center.

.The rotary abrading nib is shown or otherwise, to the reciprocating work table 12 or a part mounted thereon.

A fly-wheel effect is preferably imparted to the rotary abrading nib for maintaining, equalizing and emphasizing the rotations imparted thereto by the rotating grinding wheel. This fly-wheel effect is in the present instance produced by a fly-wheel22 fixed to the spindle 18.

The chuck is exemplified as having a socket whose lateral wall is tapered and contracts toward its inner end. The rotary abrading nib is provided with a part or shank arranged to be received in the chuck,

shown as a shank 23, whose outer periphery is tapered complemental to the tapered socket of the chuck, for being clampingly received in said chuck for fixing the rotary abrading part to the chuck and positioning the same axially with relation thereto. 7

This tapered outer periphery of the shank 23 may be on a collar 2'1 fixed about the body portion of the shank, as by means of an annular tongue and groove connection 25. This is advisable when the nature of the material of the body of the nib is such as not to adhere frictionally sufiiciently or to adhere too much to the complemental wall of the socket. For instance, if the body of the nib is formed out of hard metal, for instance, chilled cast iron, it'is advisable to provide it with a collar of softer material, for instance, Babbitt metal.

The rotary abrading nib is provided with an axial bore 31 about which the abrasive wall 16 is located. This bore preferably extends axially through the rotary abrading nib. One of the objects of providing the axial'bore is to remove the material along and adjacent to the axis of rotation of the rotary abrading nib, this axis being a neutral or non-rotating line. The presence of abrading material at and adjacent to said line might be less responsive to the abrasive action between the rotary abrading nib and the grinding wheel and form a point or portion at said axis which would have a tendency to gouge into or form detrimental marks or scores in the grinding surface of the grinding wheel being treated, and to avoid which the axial bore is provided. This axial bore preferably extends through the abrading nib and the holding shank of thenib, as for the insertion of a tool for ieady removal of the rotary abrading nib from the chuck, which may act by leverage, compression or otherwise between the inner end of the nib and the bottom of the chuck. V

The end-contact face 16 of the rotary ab'rading nib is preferably frusto-conical in form. The angular presentation of the axis of rotation of the endwise presented nib with relation to the grinding surfaces of the grinding wheel maintains such frustoconical form u on the end-contact face of the abrading n1 This end-contact face is provided with holes 32, 33, for forming cutting edges 34, 35', in said abrading face. These cutting edges act with a swirling motion upon the grinding face. The holes are preferably located at different distances from the axis of rotation of the rotary abrading nib, and

they have paths of different diameters about ing'nib. The holes more distant romthe axis of rotation of the nib are also prefer ably of-greater diameter the diameters of the holes decreasing as they approach'said axis. The holes at the inner periphery of the abrading wheel are shown as merging with the axial bore of the nib, as at 36, and the sides of the holes adjacent to the outer periphery of said. abrading wheelare shown at 37 as open at said outer periphery. The bore and the holes may be. formed when casting the body of the nib, if a casting is employed. i I

.Havin thus fully'described my'invention, what I c aim as new, and desire to secure by Letters Patent, is:

1. A rotatable abrading nib for coaction with the grinding face of irgrinding wheel, said rotatable ahrading nib having an end'. contact abrading face and holes in said endcontact abrading face atdifierent radial distances fromthe axis of rotation of said rotatable abrading nib movable in circles of different diameters across said grinding face of the-grinding Wheel. I

2. A rotatable abradin nib for coaction with the grinding face 0 i a inding wheel, said rotatable abrading nib avin an endcontact abrading face and holes 0 different diameters in said end-contact abrading face at different radial distances from the axis of rotation of said rotatable abrading nib for moving in circles of different diameters acrosssaid grinding face, said holes decreasing in diameter toward said axis of rotation.

3. A rotatable abradin nib for coaction with the grinding face 0 a grinding wheel, said rotatable nib having an end contact abrading face arranged about the axis of rotation of said abrading nib and provided with holes extending lengthwise of said axis for forming abrading walls having abrasive action on said grinding face and moving in circular paths of different diameters across said grinding face.

4. A rotatable abrading nib for coaction with the grinding face of a grinding wheel, said rotatable abrading nib having an axial bore and an abrading wall surroundingsaid bore extending lengthwise of said axis and having a conical end-contact abrading face, and said wall provided with holes whose walls form cutting edges in saidconical endcontact abrading face for abrasive action on said grinding face in a path at one side of said axis.

5. A rotatable abradingnib for coaction with the grinding face of a grinding wheel, said rotatable abrading nib having an axial bore and an abrading wall surrounding said bore extending lengthwise of said axis and having an end-contact abradin face, said Wall provided with holes exten ing lengthwise of said axis at various distances from said axis with inner ones of said holes merging with said bore, and the outer ends of the walls of said holes forming cutting edges in said end-contact abrading face for abrasive action on said grinding face.

6. A rotatable abradin nib for coaction with the grinding face of a rinding wheel, said rotatable abrading nib having an endcontact abrading wall at one end and a stem at its other end for reception in a chuck having a nib-releasing part, said end-contact wall provided with holes the walls of which form cutting edges in said end-contact abrading face, and said rotatable abrading nib provided with an axial bore for reception of a tool ast said endcontact abrading wall and said cutting edges for coaction with said nib-releasing part through said bore for release of said nib.

In testimony whereof, I have hereunto signed my name.

FERDINAND J. HOHNHORST. 

